Form apparatus



United States Patent William Leonard Smith Richmond, Virginia May 27, 1968 Nov. 10, 1970 Stewart Machine and Welding Service, Inc. Richmond, Virginia a corporation of Virginia [72] lnventor [21 Appl. No. [22] Filed [45] Patented [73] Assignee [54] FORM APPARATUS 9 Claims, 5 Drawing Figs.

144,142,155,l75,178,184,185, 66,63; 25/130(B), 128(S).1

[56] References Cited UNITED STATES PATENTS 1,516,535 11/1924 Johnson 249/144X Primary ExaminerJ. Howard Flint, Jr. Attorney-G. William King ABSTRACT: Mold apparatus is disclosed for making large tanks such as sewage or septic tanks. The apparatus is comprised of a base member with inner and outer form sections attached thereto. The inner frame is an inverted open-top box and contains a unique mechanism for moving it relative to the base member to breakaway from the material cast in the mold. A pump arrangement is adapted to force the inner form down by pressing on a substructure member built up from the base member. Springs are provided to hold and return the inner form in normal position. The outer form is comprised of sides which are hinged to the base member adapting them to be freed from the cast material.

Patented NovLlO, 1970 Sheet INVENTOR Patented Nov. 10, 1970 Sheet 2 of 2 INVENTOR "WILLIAM LEONARD SMITH ATTORNEY FORM APPARATUS In the past very complicated and expensive molding'equipment has been needed for large concrete tank casting. In addition to requiring extensive operating time and labor, prior molds have been difficult to remove from the cast concrete tank and especially from an uncured tank without causing considerable damage such as cracking, chipping, and other ill effects resulting from undue stresses and strains on the un-' cured concrete. Moreover, the prior molds have been comprised of several relatively movable parts providing many opportunities for the concrete to seep between parts and clog or make operation and good form production difficult. Some of the more pertinent prior developments are disclosed in US. Pat. Nos. 3,297,295 and 2,805,462.

The principal object of the present invention is to provide novel form apparatus for making tanks and the like, which may be manipulated by a single man in a short amount of time. It is a further object to provide such an apparatus capable of quick, easy removal from the material cast therein, yet which has very few relative moving parts and requires no dismantling from one job to the next. Briefly, the preferred apparatus of this invention is comprised of three basic elements, an inner form, an outer form and a base member. The outer form is preferably comprised of four sides hinged to the rectangular open base member and the inner form is supported in its normal position by springs bearing on a nonmovable substructure section attached to the base member. In operation, the hinged sides are held together in a vertical position while concrete is poured in the mold. To remove the form, the outer sides are pivoted down and away on their hinges and the inner form is forced down against springs normally holding the inner form in place and away from the concrete by operation of a hand pump pressurizing associated operating pistons.

Other objects and advantages of the invention will become apparent and will be described hereinafter in connection with the appended claims and description of the bestmode of carrying out the invention, and examples thereof, taken in connection with the accompanying drawings wherein:

FIG. I is a perspective view, parts broken away, of the form apparatus of the invention with concrete shown in a portion thereof; I

FIGS. 2 and 3 are elevation views in section taken through the base section of the form apparatus shown in FIG. 1 through the portions thereof shown in dotted circle lines;

FIG. 4 is a top section view of a lock mechanism for the sides of the form apparatus shown in FIG. 1 taken along the dotted circle indicated on the drawing; and

FIG. 5 is a section view in elevation taken along line 5-5 shown in FIG. 1.

Referring now specifically to the drawings, the preferred embodiment of the invention is shown. As indicated above, the apparatus is comprised of three basic elements, a base member indicated generally as 10, an inner form and an outer form indicated generally as 30.

The base is comprised of four rectangular beams 32 having a base plate 34, either solid or hollow as shown in FIGS. 2 and 3 or FIG. 5 respectively, upon which concrete is poured. The base plate top surface is either cut down or raised up as shown in FIGS. 2 and 3 or FIG. 5 respectively, depending on whether the bottom or top of the concrete tank is being cast. It is desirable to cast two substantially identical tanks except for the different form produced by the base plate, so that the two halves will fit together in tongue and groove fashion. Rigidly fixed to the base member is a substructure preferably comprised of two separate bents indicated generally as 50, located across the ends of the base section. Only one bent is shownin FIGS. 1 and 5 for purposes of illustration. However it should be understood that the structure of the apparatus at each end and in each corner is, in this preferred embodiment, the same.

Each bent 50 has a lower beam 52 fixed to and extending across the base member sides as shown in FIG. 1, and a pair of vertical upright beams 54 are fixed to and support upper horizontal beam 56. Thus beams 52, 54 and 56 are rigidly immovably fixed to the base member, and are of such size and location as to fit up into inner form near the end wall thereof. As shown in FIG. 5, upper beam 56 hangs over beams 54 at both ends. Springs 60 are located on top of these overhanging portions in each corner of the inner form.

The inner form is essentially an inverted open top, slightly 1 tapered, box of one piece construction, and consequently has no moving parts or bolted sections to increase operating difficulties. In each corner of the inner form, top and bottom bearing plates 64, 66 respectively are rigidly fixed. Spring 60 is sandwiched between plates 64 and beams 56 and are of sufficient strength 'tohold the inner forrn up in its normal position as shown in FIG. 5. Lower plates 66 each have a jack positioned thereon comprised of acylinder 70 and piston 72 and fluid line 73. A pressurizing pump, preferably a hand operable hydraulic pump ,with a pressure release valve, is attached by any suitable means to the outer side of the base. The pump is connected by fluid lines 73 running through the base member to the jacksj the location of these lines is not important and are, therefore, not illustrated. A series of cam braces are provided to assure that the inner form wall will not'deform under the weight of the concrete, or will not permit concrete to pass between itself and base member 32. Thus each brace, as shown in FIGS. 1 and 2, has a strong steel bar 82 extended across the base member and through wide slots 83 and narrow slots 84. Cylindrical cam blocks 86 are fixed to bar 82 near each end, and being spaced such that when bar 82 is extended directly across the base member, the cam blocks force the inner form walls tightly against the inner wall of base plate 34 as shown in detail in FIG. 5. A reinforced or extra thick section 20A is provided around the bottom of form 20 to further prevent deformation. A hammer block 88 is provided on the end of bar 82 extending through wide slot 83 to assist in forcing the bar and blocks 86 into a tight camming position. End cam braces are also provided at each end (FIGS. 1 and 3). They are essentially the same except that they only extend to beam 52 and not all the way through the apparatus. Thus as shown in FIG. 3, a plate 89 fixed between base plate 32 and beam 52 carries a pivot 89A for bar 82A extending through wide slot 83A and carrying cam block 86A.

In operation, to break the inner form away from the casting, the cam braces are released by hammering block 88 sideways, and cylinders 70 are pressurized causing pistons 72 to extend upward into-engagement with the bottom side of immovable beams S6. With increasing pressure thereafter, pistons 72 cause plates 66 to move downwardly carrying inner form 20 to which they are attached with them. Due to the tapered construction of the inner form side wall, as shown in FIG. 5, it is only necessary to move the inner form approximately 1 /2 to 2 inches to completely free it from the concrete casting. Commercially available pumps are preferably employed that require only a few strokes by hand to force fluid into the jacks at all four corners.

Outer form 30'is comprised of four sides hinged at 90 for breakaway movement as shown in phantom lines in FIG. 5. The sides have overlapping flanges 92 and angle bars 94 which, as shownin FIG. 4, are secured together by a bolt 96 extending therethrough and held in place by locks 98 frictionally engaging the outer edges of the flange and angle bar. Thus by hand operation of a single operator, preferably before inner form 20 is moved down as described above, bolts 96 are pivoted up and pulled out to release the outer form sides,

which may then be pulled down about hinges 90 away from the casting.

From the foregoing, it will be seen that the apparatus can be operated by an individual, contains a minimum number of moving parts and no bolts to remove, requires no turning over, employs a one-piece inner form and is generally simple and economical in construction. The latter is particularly significant in apparatus of this type, being preferably constructed of A inch steel plate and weighing approximately 3600 pounds in its finished form.

The invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore to be embraced therein.

lclaim:

1. Form apparatus comprising a rectangular, open base member and inner and outer form members positioned thereon, said inner form being adapted to fit in and move relative to said base member, said inner form being held in normal position by spring 'means contained therein and supported from said base member, and jack means operably connected with and adapted to effect relative movement of said inner form member and said base member in opposition to said spring means.

2. Form apparatus as defined in claim 1 wherein said outer form member is comprised of sides hingedly connected along form down.

6. Form apparatus as defined in claim 5 further comprising individual fluid operated jack members located in each corner of said inner form and a spring in each of said comers riding on said substructure for supporting the inner form in normal position, and pump means located on the exterior of said form apparatus and communicating with each of said jack through fluid lines.

7. Form apparatus comprising an open rectangular base member, an outer form having sides hinged along their bottom edges to said base member and being adapted to extend approximately vertical in normal position, and an inner form member in the shape of an inverted open top box fitting in said rectangular base member and adapted to move vertically relative thereto, means supported from said base member and contacting said inner form for retaining said inner form in normal position and means connected with said inner form adapted to effect vertical movement thereof against said retaining means. I

8. Form apparatus as defined in claim 7 further comprising a plurality of brace means each extending through said apparatus and adapted to contact the inner wall of said inner form and urge the same outwardly in tight sealing contact with said base member.

9. Form apparatus as defined in claim 8 wherein said brace means are each comprised of a bar extending through said base member, said bar having a pair of cam members thereon for contacting the inner wall of the inner form aforesaid when said bar is positioned directly across the base member at approximately rightangles to the sides through which it passes. 

